I have had cars that are more fun to drive (Honda S2000), larger sedans (Volvo S80), and even another Audi that I thought was my favorite car (A4 convertible), but none has been as completely the total package as this car.
The A6, while a bit blah on the exterior, is nearly perfect from the inside.
The cabin is roomy, the seats are comfortable, the electronics are helpful, and simple to use, and the fit and finish is fantastic.
The supercharged 3.0 has excellent torque at all speeds, and when the supercharged adds its punch, you best be ready to roll, quickly.
I nearly rear ended the car I intended to pass the first time I punched it.
The engine and trans are so perfectly mated.
I have owned 5 Audis over 15 years.
This A6 will be the last one.
In less than 7000 miles it has been in for repairs 6 times, including 3 times for check engine light, 1x for passenger air bag off, 1x for moldings falling off the back doors, etc.
Dealer has been helpful and supportive, unlike Audi USA who I find to be inaccessible and uncooperative.
When the car is not at the dealer being repaired it runs great as Audis do.
Watch out though for low profile tires - a silly design feature that leads to frequent blowouts when you hit one of the many potholes we have in New England.
Gas mileage of 21/30 is accurate.
You might even do a little better.
It's hard to believe there is a better car. The V8 is the ticket. Despite reviews from others, I thought the 3.0T was weak -- compared to the 4.2. And unlike the transmission mated to the V6, you can hardly feel it shift in the V8. The 3.0T has to work to accelerate. But if you can't feel the difference in your test drive, then save your money and buy the 3.0T. The 4.2 engine growls and accelerates smoothly. Unlike the 3.0T, you can't feel the vibration of the engine in the steering wheel. The fit and trim is incredible. And the lines are just breath taking. Test drove an E350, and just can't see why people pay the extra money, the A6 is hands down the better vehicle.
For the most part car is awesome and fun to drive. Fuel economy is better than I thought at 27 ave, but I do mostly highway mileage MMI Interface is easy to use and understand. Much easier than the E350 and BMW 5 series I looked at. Only issues so far after 4k miles is Check engine light came on , but went out 3 days later after I refueled. Audi said it was either gas cap issue or low octane fuel. Also MMI rebooted once while driving but reset itself. Seems to function fine Blue tooth works great with IPhone4 although Audi advises not to use 4.0 updates Sound system is great but cannot directly record CDs to Hard drive. Need to copy to MPS files first, then copy.
After driving Lexus since '94, I got rid of my '08 LS due to quality problems / high price.
I ruled out the Lexus GS because I drove one for 10 years and don't like the new ones + Lexus quality issues.
I also ruled out the MB E-class (don't like what they did with it, all the plastic in it or its price), BMW 535 (insane price) and the Hyundai Genesis (can't stand local dealers), narrowing things to Audi A6 and Infiniti M37.
The A6 is a much better performance car that is more fun to drive with styling I prefer - article on Car and Driver comparing A6, M37 and 535 is on point, particularly high RPM for M37.
I am very happy with the A6 even though M37 may be a better value to some.